mcmahon



(No Model.) 3 Sheet sSheet I;

- P. MOMAHON.

LOOK.

No. 451,878. Patented May 5,1891.

(No Model.) a Sheets-Shet 3.

P. McMAHON. LOCK.

No. 451,878. Patented May5,1891.

. Snow 50v UNITED STATES union.

ATENT- PATRICK MCMAHON, OF IVHITESTONE, NEIV YORK, ASSIGNOR TO THE YALE& TOIVNE MANUFACTURING COMPANY, OF STAMFORD, CONNECTICUT.

LOCK.

SPECIFICATION forming part of Letters Patent No. 451,878, dated May 5,1891.

' Application filed February 14:, 1391- Serial No. 381,4A6. (No model.)

To all 1071,0771, it may concern:

Be it known that I, PATRICK McMAHoN, of Whitestone, in the county ofQueens, State of New York, have invented certain new and 5 usefulImprovements in Locks, of which the following is a specification,reference being had to the accompanying drawings.

The object of my invention is to produce mprovements in master-key locksof the class I in which the tumblers are set by the rotation of a keyand not by its insertion after the manner shown, for instance, in mypatent, No. @9361, of June 3, 1890. To accomplish this object I use twosets of tumblers, one set I being actuated by the key, and these in turnactuating theother set of tumblers, which I will call thedogging-tumblers. The thickness of the key-actuated tumblers withrespect to the dogging-tumblers is such that two of the former act uponone of the latter and upon no other, so that with proper bitlngs eithera master-key or a change-key can be made to operate the look byoperating different key-tumblers. Those tumblers which I call thedogging-tumblers serve to hold the bolt in fixed relations to the casein the locked position, or alternately in the. locked and unlockedpositions, if preferred, and in order to move the bolt theclogging-tumblers 0 must be moved by the key out of engagement with itand held at a straight line of division between the two sets of tumblersuntil by the further rotation of the key the bolt may be cast orretracted. In order to accomplish this result, I may secure theclogging-tumblers in a chamber fixed to the case and locate thekey-actuated tumblers upon a movable partsuch as a platewhich actuatesthe latch or the bolt or the tail of the bolt itself, or the 4key-actuated tumblers may be made stationary, and the dogging-tumblersmay be carried upon the movable part. It is plainly immaterial which setof tumblers is made movable and which stationary so long as one set isadapted to lock'the bolt in the case.

In the accompanying drawings, Figure 1 is a plan view of my invention asapplied to a latch, showing the case with the cap-plate removed and thelatch in the locked position.

5 Fig. 2 is a similar view showing the latch in the unlocked position.Fig. 3 shows my invention as applied to a dead-bolt, the bolt beingretracted. Fig. 4 is a similar view showing the bolt in the lockedposition. Fig. 5 is a view of a modified form of my invention, showingdogging-tumblers carried on the bolt and the bolt in the retractedposition. Fig.

6 is a view of a similar modification as showing the bolt in the castposition. Fig. 7 is a vertical section through the key-hole of Fig. 5.Fig. 8 is a view of the detached parts of my invention as shown in Figs.1 and 2. Fig.

9 is a detached view of the bolt and tumblers as shown in Figs. 3 and 4.Fig. 10 is a detached view of the bolt and tumblers as shown in Figs. 5,6, and 7.

Referring now to Fig. 1 of the drawings,in which I have illustrated alatch fitted with my master-key device, A indicates the case, and B thelatch moving upon suitable bear- 7c ings therein.

C indicates a spring-actuated lever, that is pivoted to the case at Cand may be pivotally connected with the tail of the latch, and which isadapted to be operated from the inside only in the usual manner by aknob and spindle. These parts are of Well-known construction. Myinvention when applied to a latch relates to the means for operating itfrom the outside by means of keys. 8c

D indicates a carriage or movable plate adapted to be moved uponsuitable bearings in the direction of movement of the latch.

It is provided at its upper. end with a projection E, which is adaptedto engage with the lower end of the lever C, and thereby in its backwardmovement to draw the latch. In its lower part it is provided, as usual,with a recess F, within which and against the sides of which the bit ofthe key operates to move 0 the carriage.

G indicates a transverse guide-slot in the carriage,within which isfitted a guide-pin II, that projects from one side of the case andpreferably extends to the other side thereof.

I indicates another such pin, against which the top of the carriagemoves, and which assists to keep it in position.

K indicates a transverse slot in the body of the carriage, within whichis fitted the cham- IOO her-case L, that is fastened to one side of thecase integrally or otherwise and extends to the other side. Thischamber-case is narrow at one end and fits into the mouth M of the slotK, by which means the carriage is allowed to freely reciprocate withinthe casc,but within fixed limits. By reason of the guide-pin II and thechamber-case being fitted into the transverse slots the carriage iscaused to move truly and evenly under the impulse of a key, and motionmay thereby be communicated through the key to the bolt with which thecarriage engages at its upper part. Upon the top of the lower part ofthe carriage is provided a cage N, that consists of four walls securedby any suitable means to the carriage. The lower wall is cut away at N,so as to allow the free sweep of the key-bit within the cage, and isprovided in the middle of its upper side with a Vertical slot 0, whichis prolonged by projections P, extending clownwardly from said wall.Through the larger part of the chamber-case L is out a chamber orvertical slot Q of the same width as the slot 0, and so located thatwhen the latch is in the locked position the slots 0 and P form onecontinuous slot. Within the chamber Q are loosely placed a number oftumblers, which I will call dogging-tumblers B. One of these tumblers issufficient. for the practical operation of my look; but I generallyprefer to use more. The dogging-tumblers, by gravity or by the action ofsprings S, that may be wrapped around the pin H and bear at one endagainst the pin I and at the other end in slots T against the ends ofthe dogging-tumblers, tend to pass from the chamber 0 into the slot Pwhen the latch is in the locked position and so hold the carriage to thechamber-case. To separate these partsby the use of either a masterkey ora change-key, I provide Within the cage N a number of keytumblers U, twotumblers being provided for each dogging-tumbler. These tumblersconsist, preferably, of fiat pieces of metal notched at U to receive theprojections P of the upper wall of the cage, and each is provided with aprojection V of the same width as the doggingtumblers. The tumblers areof such thickness that two of them are adapted to operate one of thedogging-tumblers and no more, so that by raising any one of saidkeytumblers one of the dogging-tumblers will be raised. when thetumblers have been raised until their points of division coincide withthe line Where the upper wall of the cage and the tumbler-case meet, thecarriage will be free to move under the operation of the key until ithas retracted the latch. Then the key,

having been turned backward, may be with- Thereupon under the impulse ofthe drawn.

spring-actuated lever O the carriage will be thrown back until itreaches the position from which it started, when the chamber 0 and theslot I again coinciding the dogging-tumblers will slip from the formerinto the latter and lock the parts, as before.

From the foregoing description it will be perceived that by changing thelength of the projections V and the bits of the key a great number ofchanges in the combinations may be produced. It will also appear thattwo keys may be made to unlock the door without changing thecombination, because one keymay be made to operate the doggingtumblersthrough one set of key-tumblers and the other key may be made to operatethem through another set, and both sets of key-tumblers actindependently.

In Figs. 3 and 4 of the drawings is shown my improved construction asapplied to a deadlock. The principle is the same; but inasmuch as it isnecessary to withdraw the key both in the locked and unlocked positionsof the bolt the upper wall of the cage N is provided with two slots,into which the doggingtumblers move, and thus connect the carriage andthe tumbler chamber-case and dog the bolt.

In Fi s. 5 t3 and 7 of the drawin s is illustrated a modification of myinvention, in which the cage N and tumblers are secured to the case ofthe lock, and the dogging-tumblers are carried in a chamber-case thatforms a part of the bolt. In this instance, while the operation by thekey is precisely the same, the key-tumblers are kept transverselystationary and the dogging-tumblers are movable.

IV hat I claim is- 1. In a lock, the combination of two keyactuatedtumblers, each adapted to be set by the rotation of a key, and adogging-tumbler actuated by either of said key-tumblers, substantiallyas set forth.

2. In a lock, the combination of the two key-actuated tumblers, eachadapted to be set by the rotation of a key, a dogging-tumbler actuatedby either of said key-tumblers, and a tumbler-carriage, said carriage bythe continued rotation of the key being moved relatively to the fixedtumbler-chamber, substantially as set forth.

In testimony of all which I have hereunto subscribed my name.

PATRICK MOMAIION.

Witnesses:

W. W. BRETT, J. ll. WHITAKER.

